Gender differences in serum GH and IGF-I levels and the GH response to dynamic tests in patients with acromegaly

Nationwide survey of acromegaly in South Korea

“…In women, the prevalence was slightly higher, and this was also within the variable range as previously published reports . Mean IGF‐1 level of men was higher than that of women, which is consistent with other studies . In part, this finding explains why men were diagnosed in younger age than women, because IGF‐1 levels are known to be correlated with symptoms of acromegaly at diagnosis .…”

Gender dependence of serum soluble Klotho in acromegaly

“…In addition, women on oral oestrogens had even lower IGF‐1 levels . Regarding the relationship between age and IGF‐1 in patients with acromegaly, results of previous authors have been inconsistent . In our patients, age had no impact on IGF‐1 levels, possibly due to high IGF‐1 levels in the subgroup of oestrogen‐depleted females, which counteracted the age effect.…”

“…Considering that GH appears to have the strongest influence on sKl, our finding that sKl was higher in females may simply reflect generally higher GH levels in women, even though this did not reach statistical significance in our acromegalic patients, as in some but not all reported studies . Moreover, one may assume an influence of sex hormones.…”

“…Estimating disease activity may be difficult when the two parameters are discrepant, for example if IGF‐1 is elevated in the presence of apparently normalized GH levels; the opposite (normal IGF‐1 with high GH) may be the case in patients with liver disease, malnutrition or diabetes. Several factors influence the relationship between GH and IGF‐1, including gender and age . Healthy females produce about thrice more GH than men with similar IGF‐1 levels, suggesting that oestrogens induce a state of hepatic GH resistance…”

Genetic and clinical characteristics of Japanese patients with sporadic somatotropinoma

“…Intra-and inter-assay coefficients of variation (C.V.) for the assay of GH and IGF-I were as follows: GH (intra-C.V. 1.3% and inter-C.V. 3.3%) and IGF-I (intra-C.V. 1.1% and inter-C.V. 2.2%), respectively. Acute octreotide test (SSA test) and bromocriptine test (BRC test) were performed as previously described [12]. In brief, following the subcutaneous injection of 50 μg octreotide or the oral administration of 2.5 mg bromocriptine, serum GH level was measured every two hours until eight hours after administration.…”